List of things that decrease fertility each month?

Question

Does anyone know a list of things that decrease a couple's fertility each month and how or why they do?

Looking for things that would decrease fertility for any given month, not particularly long term stuff.

But all answers are appreciated !

Thanks.

Answer 1

all lubricants except for preseed kill sperm, condoms and birth control pills are about the only things that will ensure you wont get pregnant without any long term effects.

wait, are you trying to get pregnant or not trying to get pregnant?  your question wasnt very clear.

Answer 2

being too heavy or skinny

stress

not eating right

men wearing tight underwear

men taking too hot of showers

taking prenatal vitamins while trying to get pregnant are always a good idea, i think that they increase your fertility by making your body healthier